The invention relates to low profile lighting for use, for example, as a vehicle headlamp.
In general, as shown in FIG. 23, a headlamp 900 may have a reflector 905, a lens 910, and a light source 915. The light source 915 may be located at a primary focal point 920 of the reflector 905. If the reflector 905 is parabolic in shape and the light source 915 is located at the primary focal point 920, then the light rays 925 reflected from the reflector 905 will be parallel. Therefore, the size of the lens 910 will need to be approximately equal to the cross-sectional area of the reflector 905.
FIG. 24 shows a side cross-section view of an elliptical reflector 950. The elliptical reflector 950 provides some narrowing of the beam spread in the vertical plane as indicated by the converging paths of the reflected light rays 925. The top cross-section view of FIG. 25 shows that the elliptical reflector 950 provides an even greater reduction in beam spread in the horizontal plane. Therefore, the elliptical reflector 950 allows the size of the lens 955 to be reduced in the vertical and horizontal planes.
Projection headlamp systems have been used to reduce headlamp lens size. A projection headlamp generally includes a light source, a reflector, and a single condensing lens. A light shield is positioned between the light source and the lens or between the light source and the reflector to help shape the desired far field beam pattern. Due to the high temperatures associated with projection headlamps, resulting from the concentration of all of the light in the center of a single lens, the lens generally is made of glass. Projection headlamps tend to be expensive and incompatible with conventional headlamp manufacturing techniques.
A low profile light, such as a vehicle headlamp, has a lens that is smaller in area than the lens of a conventional light and is significantly smaller in area than the reflector of the light. These configurations allow automobile and other designers to achieve aesthetic styling and improved aerodynamics. The low profile light increases design flexibility by employing a multi-section reflector for which each section can be directed individually. The low profile design techniques also may be applied to turn signals and other vehicle lights, as well as to other general lighting applications.
A low profile vehicle headlamp includes a reflector, a source and a lens. The headlamp is configured so that light from the source reflects from the reflector and is output from the headlamp through the lens. Concave reflector sections are formed by dividing the reflector. Each reflector section has a primary focal point and primary axis. The primary focal points of the reflector sections are coincident and the primary axes of the reflector sections are angled with respect to one another.
Other features and advantages will be apparent from the following description, including the drawings, and from the claims.